Solid state lighting panels may be used as solid state backlight units for displays, as lighting panels for general illumination, as backlights for signage, and/or for other purposes. Solid state backlighting units for LCD displays typically include a two dimensional array of discrete light sources arranged behind an LCD screen. The discrete light sources may generate light having a white or near-white color that may be used to illuminate an LCD display, such as a full-color LCD display. In order for the LCD display to display an image on the screen having uniform color and/or intensity, it may be desirable for the backlight unit to provide a light to the LCD screen that is spatially uniform, both in color and intensity. This may be difficult, however, as the discrete light sources may be spaced apart from each other in the backlight unit. In particular, as the brightness of solid state light sources increases, it may be desirable to arrange the light sources with a larger and larger pitch between sources, for example, in order to reduce heat dissipation and/or to increase the efficiency of the display.
Similar problems relating to color uniformity, efficiency and/or heat dissipation may arise when solid state lighting units including arrays of solid state light emitting devices are used for general illumination.